Electrical plug with cord anchor



May 2, 1967 ELECTRICAL PLUG WITH CORD ANCHOR Filed Sept. 9. 1964 5 Sheets-Sheet 1 H. P LYNCH 3,317,834

INVENWTOR I ATTORNEY May 2, 1967 H. P. LYNCH ELECTRICAL PLUG WITH CORD ANCHOR 5 Sheets-Sheet 2 Filed Sept. 9. 1964 y 2, 1967 I H. P. LYNCH 3,317,884

ELECTRICAL PLUG WITH CORD ANCHOR Filed Sept. 9, 1964 s Shets-Sheet 3 FIG. 5

I United States Patent Filed Sept. 9, 1964, Ser. No. 395,156 4 Claims. (Cl. 339106) This invention relates to electrical plugs or sockets, and more particularly, to cord-anchoring means. i

The invention is embodied within the combination of an electrical plug and an electrical cable. The latter includes a plurality of insulated electrical conductors and a shaped rigid anchor attached to the cable near one of its ends. The plug comprises a body member that includes a cord guide chamber and a plurality of electrical prongs that are removably mounted in the body-in a predetermined geometric pattern. The prongs extend from the 'body and are adapted to inter-fit with an'appropriately shaped socket. Each prong includes a connector on one end that is adapted to receive an electrical conductor from the cable.

The plug further includes a cap that is appropriately shaped to fit over the body, thus forming an enclosure or cavity. The chamber opens into the cavity and provides an access to the cavity from the outside.

Interposed between the cap and the body in the cavity is a conductor tip guide that guides the ends of each electrical conductor of the cable into electrical and physical contact with the prongs. The cord guide chamber includes a bridge member that cooperates with the cable anchor to securely fasten the cable to the plug'body in the chamber.

The illustrative plug has been designed to overcome the problem caused when axial forces are exerted upon the cable. In order to insure good electrical and physical connections between the individual conductors of the cable and the electrical prongs, it is necessary that any forces transmitted to the cable beisolated from the connections between the conductors and the electrical prongs. Forces exerted upon the cable may tend to break these connections thus resulting in open circuits or interrupted electrical continuity.

It is known within the prior art to solve this problem by using a guide chamber in which the incoming cable is knotted or tied around a rigid member of the plug body. The tying of such a knot requires considerable and expensive installer time and results in a bulky, inefiicient package. It is also known to make the electrical connections between the conductor ends and the prongs of sufficient mechanical strength to withstand any forces exerted on the cable member. This results in an enlarged structure that may be sound from a mechanical stand-point but is inefficient, expensive, and impractical from an electrical design standpoint.

The illustrative embodiment of the invention securely anchors the cable to the body member and thus any forces exerted upon the cable are applied to the plug body.

Thus, the connections between the individual conductors of the cable and the electrical prongs are insulated from any forces exerted on the cable and are therefore not interrupted or broken by the forces. The connections, as a result, may 'be designed purely from an electrical standpoint using known quick connect, efficient electrical methods.

plugs or sockets that include J As shown in FIG. 1, the illustrative embodiment of Pr I 3,317,884 Patented May 2, 1967 ice . dition;

FIG-3 is a section view showing the interconnection between one conductor of the cable and an electrical FIG. 4 is'a section view taken generally along the line 4-4 of FIG. -2 showing a different anchoring device from that shown in FIG. 2; and

FIG. 5 is a section view taken generally along the line 4-4 of- FIG. 2 in which a different anchoring device from that shown in FIGS. 2 and 4 is shown.

the invention comprises aplug body member 10 in which a plurality of electrical prongs 11 are removably mounted in any desired geometric pattern. The prongs 1.1 are adapted to interfit with a socket member that is not shown. One end of each prong 11 includes at least one spring connector 12 and, as shown in FIG.- 1, may include two spring connectors 12; The connectors 12 are formed from a strip of electrically conducting material that is rigidly fastened to the prong 11 by-means of brazing,

soldering, or otherwell known fastening means. The ends of the connectors 12 are reversely bent back toward themselves to define a receiving passage whose function will subsequently be described. r

The plug further includes a cap14 that is shaped to fit over the body member 10 and-to be secured thereto by 'means of a threadedfastener36 as illustrated in FIG. 2. The cap '14 forms an enclosure or cavity 35 with the body ,member 10 and further includes a projection 15 that is adapted to mate with a projection 16 on the member 10. The projections 15 and 16 of the cap 114 and the body member 10, respectively, are hollowed out to form a cord guide chamber 13. An electrical cable 17 communicates with the inside of the plug through the chamber 13.

The chamber 13 includes an indentation 18 that is adapted to receive a tab 19 on the cable anchor 20, and two mounting slots 21 that are shaped to receive two arms 22 of a cable anchor fastener23. The fastener 23 ,may include two locking arms 37 that are adapted to snap into two grooves 38 located in the chamber portion ,of the projections 16. Thus, when the arms 22 of the -fastener'23 are inserted in the slots 21 of the projection 16, the fastener 23 will be locked to the body member 10 and will require aconsiderable force to pull the locking arms 37 out of the grooves 38 in order to remove the fastener 23- from the member 10. The projection 15 of the cap 14 interfits with the projection 16 of the body member 10 to further insure and hold the fastener 23 over the anchor 20 and in contact with the projection 16 of'the body 10. Y a

Interposed between the cap 14 and the body member 10 is a conductor tip guide 24. As shown in FIG. 1 the illustrative embodiment contemplates that each electrical conductor 25 of the cable 17 will terminate in a spade 5 6 said passage having cord restricting means shaped and References Clted by the Exammer adapted to cooperate with said anchoring means to pre- UNITED STATES PATENTS vent relative motion of said anchoring means with respect 2,226,610 12/ 1940 Heyman 339-106 X to said element, said passage further including holding 5 2,234,926 3/1941 Jepson 339-106 X means, said last mentioned means located adjacent said 2,258,343 10/ 1941 Walker 339106 restricting means and adapted to hold said anchoring FOREIGN PATENTS means In COOPBIEIHVB relationship with said restr1ct1ng 495,193 4/1930 Germany. means, and said element further including guide means, said guide means adapted to guide said tips into physical 10 MARVIN CHAMPION, 'y Exammerand electrical contact with said terminals. LFRED S. TRASK, Examiner. 

1. A PLUG, IN COMBINATION WITH AN ELECTRICAL MULTICONDUCTOR CORD, SAID PLUG COMPRISING A MATING CAP PORTION AND A BODY MEMBER, THE LATTER INCLUDING A PLURALITY OF ELECTRICAL TERMINALS, SAID PORTION AND SAID MEMBER EACH HAVING A TROUGH SECTION, SAID SECTIONS WHEN SAID PORTION AND SAID MEMBER ARE MATED FORMING A CORD ACCESS PASSAGE, THE ENDS OF THE INDIVIDUAL CONDUCTORS OF SAID CORD EACH HAVING AN ELECTRICAL CORD TERMINAL TIP, SAID CORD INCLUDING ANCHORING MEANS INCLUDING AT LEAST ONE PROJECTING MEMBER AXIALLY SPACED FROM THE TERMINAL TIP ENDS OF SAID CORD, A TROUGH SECTION OF SAID MEMBER INCLUDING A SLOT AND ATTACHING MEANS, SAID SLOT BEING ADAPTED TO RECEIVE SAID PROJECTING MEMBER OF SAID ANCHORING MEANS, CORD RESTRICTING MEANS ATTACHED TO SAID MEMBER BY SAID ATTACHING MEANS AND HOLDING SAID PROJECTION IN SAID SLOT, AND, GUIDE MEANS INTERPOSED BETWEEN SAID PORTION AND SAID MEMBER, SAID LAST-MENTIONED MEANS GUIDING SAID TERMINAL TIPS INTO PHYSICAL AND ELECTRICAL CONTACT WITH SAID TERMINALS. 